I opened php.ini and .htaccess files and put it in the directory "wp-includes". But I have result only changing the in end of "Fatal error" massage, - number of line (1486 >> 5410):

I have now new massage:
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 1966080 bytes) in /home/nsige/public_html/wp-includes/class-simplepie.php on line 5410

+ I was informed form hoster that PHP Configuration > memory_limit 24M is unreal and I must open own php.ini in directori to take full memory resources (but <200M). I open php.ini (+ .htaccess in directory wp-includes) and insert there 128M

I think allso, that my Data base is full or not ;( (with red collor in cPanel)...

That's not going to be related to W3TC. That is a networking or hosting issue - the test system is having intermittent trouble connecting to your server. I spot checked a few other tests from Dulles and don't see similar issues. You should reach out to your hosting provider to see if they are having any issues.

ou a simple file PHP.INI ? and had been guilty of?
ou I can't imagine this solution !

Many, many thanks to you iliketheride, you can not imagine how much I was looking for the solution of this problem. as well that I waited for your good advice. Many thanks also to this forum, and specifically Mr Pat :)